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	Wet-only deposition of atmospheric inorganic nitrogen and associated isotopic characteristics in a typical mountain area, southwestern China 期刊论文 OAI收割 SCIENCE OF THE TOTAL ENVIRONMENT, 2018, 卷号: 616, 页码: 55-63 作者: Leng, Qiangmei; Cui, Jian; Zhou, Fengwu; Du, Ke; Zhang, Liuyi \| 收藏 \| 浏览/下载：41/0 \| 提交时间：2018/03/16 Nitrogen wet deposition Nitrogen isotope Nitrogen source Chongqing Compared research
	Evaluation of spatial upscaling methods based on remote sensing data with multiple spatial resolutions (EI CONFERENCE) 会议论文 OAI收割 Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states Ren R.; Gu L.; Cao J.; Chen H.; Sun J. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In most applications of remote sensing data special spatial information is required from a finer to a coarser spatial resolution with appropriate upscaling methods. The purpose of this paper is to compare and evaluate current spatial upscaling methods using MODIS remote sensing data with multiple spatial resolutions. In the research Northeast China was selected as the study area. MODIS data with spatial resolutions of 250 m (2 bands) and 500 m (7 bands) were used as the test data. Through using the selected upscaling methods the Band 1 and Band 2 data of MODIS were scaled up from 250 m to 500 m spatial resolution. On the basis of land cover characteristics of Northeast China the MODIS data located in the study area was classified into the five land cover types including water grasslands forests farmlands and bare lands using maximum likelihood method. The land cover classification results were further compared with MODIS Land Cover Type product. Finally Structural Similarity (SSIM) was selected to evaluate the effects of these upscaling methods. The research can provide more useful information for spatial scaling transformation in remote sensing data applications. 2012 SPIE.
	AUTONOMOUS INTEGRATED NAVIGATION USING X-RAY PULSARS AND ASTEROIDS 会议论文 OAI收割 63rd International Astronautical Congress 2012, IAC 2012, Naples, Italy, 2012 Yang Chengwei; Gao Dong; Zheng Jianhua 收藏 \| 浏览/下载：39/0 \| 提交时间：2014/04/30 To improve the navigation performance of the spacecraft during interplanetary cruise a novel integrated navigation system is proposed. For X-ray pulsar navigation (XNAV) is a hot and prospective research subject and the optical navigation using asteroids is practical in space engineering we designed an autonomous navigation system using one X-ray detector and one navigation camera. The measurement models of the XNAV based on the time difference of arrival and the optical navigation based on the images of asteroids are presented. To enhance practicality the X-ray pulsars and asteroids are observed by turns. The batch least square filter used by Deep Space I is adopted to estimate the system state. The numerical simulation results show that the integrated navigation is feasible on the interplanetary cruise orbit. Moreover compared with the XNAV and the optical navigation the integrated navigation system can provide higher navigation performance.
	The effect of backlash nonlinear on resonance frequency of electric actuator transmission system (EI CONFERENCE) 会议论文 OAI收割 3rd IEEE International Conference on Advanced Computer Control, ICACC 2011, January 18, 2011 - January 20, 2011, Harbin, China Han X.; Ge M.; Bai Y.; Jia H.; Ge W. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 In order to study the effect of backlash nonlinear on resonance frequency of electric actuator transmission system then Finally in the premise of meeting the stability the dynamic equilibrium equation of transmission system with backlash is established it makes dynamic simulation analysis for the transmission system based on virtual prototype technology it establishes balanced equation of dynamics system with backlash the effect of backlash on system natural frequency and resonance frequency and the theoretical values and simulation values are compared. Theoretical analysis and simulation results show that the theoretical analysis is basically consistent with simulation results when it is zero backlash and does some theory research and dynamic analysis of backlash nonlinearity and system natural frequency and resonance frequency. First and the error of theoretical analysis and simulation results is within 10%. Therefore according to describing function to theoretically model the backlash nonlinear it can be concluded that considering the transmission system theoretical analysis of backlash nonlinearity is feasible the relation between describing function and the amount of backlash and input amplitude is analyzed and it is much closer to the actual system with instructive significance. 2011 IEEE.
	Application of particulate reinforced aluminum matrix composite in airborne photoelectric turret (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China 作者: Wang P. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 In order to design and manufacture more excellent airborne photoelectric stable turret modulus of elasticity of 213 GPa and thermal expansion coefficient of 7.9106/K. The frame has decreased the maximum deformation by by 60% and increased the fundamental frequency by 65% as compared with those of aluminum alloy materials a new type of aeronautical material-particulate reinforced aluminum matrix composite (SiC/Al composite) is investigated. Several crucial technologies respectively as shown by finite element analysis results. Those are confirmed by vibration test furthermore. Therefore such as pressureless infiltration technology a significant lightening effect is achieved and the thermal control load is also reduced. The test result indicates that the stable accuracy of the system achieves 19.8rad and the optical-axis parallelism of pay load is 0.1mrad. The research applies the SiC/Al composites to airborne photoelectric platforms interface reaction controls and plate's welding are systematically studied. Then which makes a effective exploration for the new aeronautical material's application. 2011 IEEE. using SiC/Al composites the airborne photoelectric stable turret frame is successfully prepared in density of 2.94 g/ cm3
	A study on atmospheric turbulence effects in full-optical free-space communication systems (EI CONFERENCE) 会议论文 OAI收割 2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China 作者: Liu P. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 Next generation free-space optical communication systems have used fiber-optic technology as the seamless connection between free-space and optical fiber. The full-optical free-space optical communication systems use optical fiber as the receiver to get faster communication speed. The atmospheric turbulence deeply influenced on the optical wave propagated in terrestrial application. As the active receiving area of the full-optical free-space optical communication systems is very small it is important to research on the atmospheric turbulence effects on the full-optical free-space optical communication system. In this paper we discuss about both the turbulence-induced intensity fluctuations and the angle-of-arrival effects in full-optical free-space optical communication systems which are used in a few kilometers communication. We gave the numerical results of the atmosphere turbulence effects on the free-space optical communication systems. In order to minimize the atmospheric turbulence influence on the full-optical free-space optical communications system we also investigate the use of fine tracking system in the communication system. We have set up a full-optical free-space communication system in Tokyo and received useful data from the experiment. We compared the receiving power of the experiment when the fine tracking system is On and Off. From the experiment results we can see that the fine tracking system effectively mitigates the atmospheric turbulence and increases the receiving power of the communication system. 2010 IEEE.
	The calibration of faint simulation star magnitude based on single photon count technique (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Imaging Detectors and Applications, June 17, 2009 - June 19, 2009, Beijing, China 作者: Xu S.-Y.; Guo J.; Guo J. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 A calibration method of faint star magnitude of the star scene simulation device is proposed in this paper. In the research of simulation star magnitude luminometers and CCD devices are the general calibration devices which are used to measure the illumination intensity and calibrate its magnitude. But if the simulation magnitude is only sixth magnitude its illumination intensity is only 1.010-8 Lux. This illumination intensity level is the lowest illumination intensity that the commercial luminometer can detect. Hence the simulation star magnitude lower than six magnitude cannot be calibrated by luminoters. Likewise CCD devices also need an additive cooler in this case. When the single photon characteristic is presented due to the low luminosity of simulating light sources the simulation star magnitude can be calibrated by detecting its photon flux of radiation with the method of single photon count. In this paper the detection principle of single photon based on a compact designed PMT detecting of the radiation level of simulation star magnitude is advanced. Especially a spectrum match method is proved theoretically to be an effective means for selecting PMT photosensitive type. In the case of the detection object of the simulation star in visible wavelength a analysis indicates that the material of tri-alkali cathode materials its best choice after being compared the Signal-to-Noise of photon detector of several PMT photosensitive materials based on the different spectrum match ratio of different object light sources and different cathode materials. An experiment is employed to show the relationship of control voltage of PMT and its dark counter the relationship of the environment temperature of PMT and its dark counter which proves its only decades of CPS at room temperature. The so low dark counter avoids a bulky cooler and is convenient for installing it on the star scene simulation equipment. Finally in the experiment of calibrating the simulation star magnitudes the ability of its calibration is confirmed to reaches up to 12m meanwhile its calibration error is within 0.2m. 2009 SPIE.
	Heterogeneous architecture-based software reliability estimation: Case study (EI CONFERENCE) 会议论文 OAI收割 3rd International Conference on Convergence and Hybrid Information Technology, ICCIT 2008, November 11, 2008 - November 13, 2008, Busan, Korea, Republic of Wei Y.; Shen X.-H. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 With growing system complication multiple structures are constructed in software instead of single architecture style. As a result the traditional architecture-based models that have considered only homogeneous software behaviors are not suitable to the complex system. In this paper a heterogeneous architecture-based model is presented. In order to verify the practicability we apply the model to estimate the system reliability of the astronautics payload communication and monitoring system (APCMS). Multiple structures are constructed in the system i.e. sequence parallel and fault-tolerance. The study results demonstrate that the model is accurate when compared to the actual reliability. Theoretical research must be applied on actual systems to understand their applicability and accuracy. 2008 IEEE.
	BP neural network application on surface temperature measurement system based on colorimetry (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Sun Z.-Y. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 Measurement of the features of infrared radiation is very important for the precaution and discrimination of missiles and relevant research is worthy in military application. The measurement of target's surface temperature is the foundation of infrared radiation characteristics measurement. The principle and configuration of target's surface temperature measurement system based on colorimetry is introduced the measurement model is deduced and the processes of temperature measurement are presented. Least-square method and back-propagation neural network method are both used to deal with the demarcating data. Compared with the least-square method Back-propagation neural network has more advantages such as high precision good applicability and so on.